Digital Commons Network^™

Efficient Schemes To Evaluate Transaction Performance In Distributed Database Systems, R. Mukkamala, S. C. Bruell

Computer Science Faculty Publications

Database designers and researchers often need efficient schemes to evaluate transaction performance. In this paper, we chose two important performance measures: the average number of nodes accessed and the average number of data items accessed per node by a transaction in a distributed database system. We derive analytical expressions to evaluate these metrics. For general applicability, we consider partially replicated distributed database systems. Our first set of analytic results are closed-form expressions for these two measures. These are based on some fairly restrictive simplifying assumptions. When these assumptions are relaxed, no closed-form expressions exist for these averages. Hence, we develop …

Role Of Term Symmetry In E-Completion Procedures, Ralph W. Wilkerson, Blayne E. Mayfield

Computer Science Faculty Research & Creative Works

No abstract provided.

Computational Intelligence In Cad/Cam Applications, Chaman Sabharwal, Thomas G. Melson, Martin D. Fraser

Computer Science Faculty Research & Creative Works

This paper presents a fundamental, direct, and powerful approach to the surface/surface intersection problem in CAD/CAM applications. The algorithm is designed and implemented in three steps: a) Preprocessing- locate the potentially intersecting sections of the surfaces and decompose the surfaces into surface elements within specified flatness tolerance; b) Intersection- decompose the possibly intersecting pairs of surface elements into continuous surface triangulations to find the approximate intersections between the pairs of surface elements; c) Postprocessing-assemble the intersection primitives into curves of intersection, refine the accuracy of computed intersection points, and compact the intersection curves. This surface/surface intersection algorithm is applicable to …

Distributed Evaluation Of An Iterative Function For All Object Pairs On A Simd Hypercube, Fikret Erçal

Computer Science Faculty Research & Creative Works

An efficient distributed algorithm for evaluating an iterative function on all pairwise combinations of C objects on an SIMD hypercube is presented. The algorithm achieves uniform load distribution and minimal, completely local interprocessor communication.

Performance Improvements For Fddi And Csma/Cd Protocols, David Earl Game

Computer Science Theses & Dissertations

The High-Performance Computing Initiative from the White House Office of Science and Technology Policy has defined 20 major challenges in science and engineering which are dependent on the solutions to a number of high-performance computing problems. One of the major areas of focus of this initiative is the development of gigabit rate networks to be used in environments such as the space station or a National Research and Educational Network (NREN).

The strategy here is to use existing network designs as building blocks for achieving higher rates, with the ultimate goal being a gigabit rate network. Two strategies which contribute …

Data Security: The Securing Of Computer Installations And Data Sets, Willy B. Kuehnle

Theses

No abstract provided.

Design Of A Dynamically Reconfigurable, Integrated, Parallel Vision System, Ashok K. Samal

School of Computing: Conference and Workshop Papers

Multiprocessors can be used to speed up the process of object recognition. Building a parallel vision system is a two step process: (a) design and implement parallel algorithms for individual operations, and (b) integrate them into a coherent system. So far the emphasis has been on the first step. The second step has not received enough attention. A framework for building a parallel vision system is presented here. The necessary and desirable features of such a system have been identified. An initial design which incorporates these features is also given.

An Experimental Study On Reject Ratio Prediction For Vlsl Circuits: Kokomo Revisited, Dharam Vir Das, Sharad C. Seth, Paul T. Wagner, John Anderson, Vishwani Agrawal

School of Computing: Faculty Publications

Assuring product quality is becoming increasingly more important for the semiconductor chip manufacturers. The reject ratio (defect level) provides a simple and accurate measure of a product's quality. However, measuring the reject ratio of tested chips is often not feasible or accurate. Statistical techniques for reject ratio prediction provide a possible way out of this dilemma. In this paper, we report on an experiment to verify the accuracy of reject ratio predictions by the available approaches. The data collection effort includes instrumenting the wafer probe test to obtain chip failures as a function of applied vectors and running a fault …

Trellis-Coded Multidimensional Phase Modulation, S. S. Pietrobon, Robert H. Deng

Research Collection School Of Computing and Information Systems

A 2L-dimensional multiple phase-shift keyed (L×MPSK) signal set is obtained by forming the Cartesian product of L two-dimensional MPSK signal sets. A systematic approach to partitioning L×MPSK signal sets that is based on block coding is used. An encoder system approach is developed. It incorporates the design of a differential precoder, a systematic convolutional encoder, and a signal set mapper. Trellis-coded L×4PSK, L×8PSK, and L×16PSK modulation schemes are found for 1⩽L⩽4 and a variety of code rates and decoder complexities, many of which are fully transparent to discrete phase rotations of the signal set. The new codes achieve asymptotic coding …

Exclusive And Inclusive Decays Of B Mesons Into Ds Mesons, D. Bortoletto, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

We have studied the production of Ds mesons in the decays of B mesons at the Υ(4S) resonance. We report on the first observation of exclusive B-meson decays B->Ds−D*+, B→Ds−D+, and B→Ds−D0. We also present a new measurement of the branching ratio and the momentum spectrum for the inclusive decay B→DsX.

Measurement Of The C+ Decay-Asymmetry Parameter, Avery, P.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

We report a measurement of polarization in the two-body decay c+, in nonresonant e+e- interactions from data taken with the CLEO detector. Using these data we have determined the parity-violating asymmetry decay parameter c to be -1.0-0.0+0.4. We see no evidence for significant c+ polarization.

Observation Of B-Meson Semileptonic Decays To Noncharmed Final States, Fulton, R.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

No abstract provided.

Observation Of Iv(4=S) Decays Into Non-=Bba Final States Containing I Mesons, Alexander, J.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

We report on the observation of ; mesons from T(4S) decays which are too energetic to come from 8 mesons. These events provide evidence for non-88 decays of the T (4S). The measured rate is B(T(4S)+fX)=0.22•0.06•0.041 for ; momentum above 2 GeV/c.

Computer Vandalism And The Law, Eugene H. Spafford

Department of Computer Science Technical Reports

No abstract provided.

Experimental Facility For Kernel Extensions To Support Distributed Database Systems, Bharat Bhargava, Enrique Mafla, John Riedl

Department of Computer Science Technical Reports

No abstract provided.

Efficient Geometric Algorithms In The Erew-Pram, Danny Z. Chen

Department of Computer Science Technical Reports

No abstract provided.

Ua66/3/2 Computer Science Alumni Newsletter, Vol. 5, Wku Computer Science

WKU Administration Documents

Newsletter created by WKU Computer Science for the alumni of the program.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, November 1989, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A sixteen page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

On The Height Of Digital Trees And Related Problems, Wojciech Szpankowski

Department of Computer Science Technical Reports

No abstract provided.

A Hierarchical Approach To Concurrency Control For Multidatabases, Ahmed K. Elmagarmid, Yunhho Leu

Department of Computer Science Technical Reports

No abstract provided.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, October 1989, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A fourteen page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

High Rate Concatenated Coding Systems Using Multidimensional Bandwidth Efficient Inner Codes, Robert H. Deng, Daniel J. Jr. Costello

Research Collection School Of Computing and Information Systems

A concatenated coding system using two-dimensional trellis-coded MPSK inner codes and Reed-Solomon outer codes for application in high-speed satellite communication systems was proposed previously by the authors (ibid., vol.37, no.5, p.420-7, May 1989). The authors extend their results to systems using symbol-oriented, multidimensional, trellis-coded MPSK inner codes. The concatenated coding systems are divided into two classes according to their achievable effective information rates. The first class uses multidimensional trellis-coded 8-PSK inner codes and achieves effective information rates around 1 b/dimension (spectral efficiency 2 b/s/Hz). The second class employs multidimensional trellis-coded 16-PSK inner codes and provides effective information rates around 1.5 …

Design Considerations For Distributed Scientific Software Systems, Paul E. Buis

Department of Computer Science Technical Reports

No abstract provided.

Analysis Of Digital Tries With Markovian Dependency, P. Jacquet, Wojciech Szpankowski

Department of Computer Science Technical Reports

No abstract provided.

A Note On The Height Of Suffix Trees, Luc Devroye, Wojciech Szpankowski, Bonita Rais

Department of Computer Science Technical Reports

No abstract provided.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, September 1989, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A twelve page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Optimal Canonization Of All Substrings Of A String, A. Apostolico, M. Crochemore

Department of Computer Science Technical Reports

No abstract provided.

Implementing Object Support In The Raid Distributed Database System, Bharat Bhargava, Prasun Dewar, James G. Mullen, Jagannathan Srinivasan

Department of Computer Science Technical Reports

No abstract provided.

Embedding Meshes On The Star Graph, Sanjay Ranka, Jhy-Chun Wang, Nangkang Yeh

Electrical Engineering and Computer Science - Technical Reports

We develop algorithms for mapping n-dimensional meshes on a star graph of degree n with expansion 1 and dilation 3. We show that an n degree star graph can efficiently simulate an n-dimensional mesh.

Multiple Network Embeddings Into Hypercubes, Ajay K. Gupta, Susanne E. Hambrusch

Department of Computer Science Technical Reports

No abstract provided.